The invention relates to a damping arrangement for guide vanes, in particular for guide vanes of a gas turbine or an aircraft engine.
Gas turbines consist of several assemblies, for example, among other things, a fan, a combustion chamber, preferably several condensers, as well as several turbines. Referring to the preferably several turbines, these are one high-pressure turbine and one low-pressure turbine; referring to the several condensers, these are one high-pressure condenser, as well as one low-pressure condenser. Inside a turbine, as well as inside a condenser of a gas turbine, several guide vane rings are arranged in a row in axial direction or in flow direction, in which case each guide vane ring comprises guide vanes distributed over its circumference. Between each two adjacent guide vane rings, respectively one rotor blade ring is provided, this latter rotor blade ring comprising several rotor blades. The rotor blades are associated with a rotor and rotate, together with the rotor, relative to a stationary housing, as well as relative to the also stationarily configured guide vanes of the guide vane rings.
In particular, the guide vanes of compressors of a gas turbine are subject to vibrations during operation of the gas turbine, so that the guide vanes must be damped in order to avoid damage to the guide vanes. Prior art has already disclosed the damping of guide vanes on their inner shroud, in that a spring element is installed in a hollow space between the inner shroud of the guide vanes and a seal bearing. Referring to prior art, in so doing, C-shaped springs are used, the springs having a relatively large radial design height. As a result of this, the radial dimension of the gas turbine is enlarged. Furthermore, the manufacture of prior art spring elements is relatively complex, and, due to bending operations required in the course of the manufacture of the spring elements, they are subject to tolerances. This is an overall disadvantage.
Considering this, the object of the present invention is to provide a novel damping arrangement for guide vanes, in particular for the guide vanes of a gas turbine or of an aircraft engine.
In accordance with the invention the, or each, spring element is configured as a leaf spring, in which case the, or each, spring element configured as a leaf spring exhibits a minimal radial extension.
Within the meaning of the present invention, it has been suggested that leaf springs be used as spring elements. The leaf springs are clamped between the inner shroud of the guide vanes and the, or each, seal bearing. This results in a clear reduction of the radial design space required for damping and thus in a clear reduction of the radial dimensions of the gas turbine. Such spring elements configured as leaf springs can be manufactured in a cost-effective manner and are less subject to tolerances than the C-shaped spring elements used for damping in prior art.
Preferably, the, or each, spring element configured as a leaf spring is clamped between the inner shroud of the guide vanes and the, or each, seal bearing, in which case the leaf spring's central abutment section abuts against the, or each, seal bearing and the leaf spring's two lateral abutment sections abut against the inner shroud of the guide vanes. Also, it is possible that the leaf spring's central abutment section abuts against the inner shroud of the guide vanes and the leaf spring's two lateral abutment sections abut against the, or each, seal bearing.
Referring to an advantageous development of the invention, the, or each, spring element configured as a leaf spring, comprises several leaf spring sections divided by slits, in which case each inner shroud of each guide vane is associated with such a leaf spring section, abutting against this leaf spring section.